SORÇÃO SIMULTÂNEA DE Al, Cu e Cr UTILIZANDO RESÍDUO DE MOINHA DE CARVÃO ATIVADO

Abstract

The presence of metal ions in wastewaters at high concentrations and their impacts have been objects of environmental research primarily due to toxicity of these elements and the cumulative properties of the same food chain. Producing activated carbon industry generates a residue in the grinding step of charcoal. This residue called "chaff activated carbon" has different characteristics than activated carbon sold by owning a high ash content which can interfere with the quality of the final product, so totally discarded in landfills. A preliminary characterization of this waste made by industry according to ABNT NBR 10004 classified the waste as Class IIB, in other words, the residue is classified as inert. Waste characterizations showed the solid has adsorptive characteristics with available surface area capable of adsorbing Cu2+, Cr6+ and Al3+ions in waste water. At concentration of 32.0 g/L of residue removal efficiency of ions in solution was 98% for Cu2+ and Cr6+ and 99% for Al3+. Simultaneous sorption showed better removal efficiencies at pH 4 and the sorptionequilibrium occurs in the first minutes of contact time, even for high concentrations of metal ions. The initial concentration of ions in the solution was the variable that had the greatest effect on the results. The residue showed as a promising application in real sample doped water with metal ions, effectively removing the metal ions without significant influence of other contaminants in the raw water.